


In A Mirror, Darkly

by GoodTimesNewRoman



Category: Undertale (Video Game)
Genre: Gen, POV Third Person
Language: English
Status: In-Progress
Published: 2016-05-10
Updated: 2016-05-10
Packaged: 2018-06-07 14:48:52
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,092
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6809791
Author URL: https://archiveofourown.org/users/GoodTimesNewRoman/pseuds/GoodTimesNewRoman
Summary: <blockquote class="userstuff">
              <p>The Royal Scientist disappears.</p>
            </blockquote>





	In A Mirror, Darkly

 

*

A surprising amount of the best—and worst—scientific discoveries are made by accident. For the longest time, Sans had never appreciated that fact, because generally, nothing was ever an _accident_ with W.D.

Try and put it into perspective: one monster—secretly, all by himself—comes up with a design for a machine that could potentially supply electricity to the entire Underground. The theory is sound, it accounts for the limited, outdated technology available to them— _ice cubes, bro?_ —and when they put it together after months and months of effort, it works.

It works.

Just picture it for a second. December, college students arrive with lamps in hand, and anyone who knows fire magic is everyone’s best friend. January—new year, new beginnings—and they’re installing light bulbs in every building. The price of TVs, cell phones and all the other human junk skyrockets, because people can now _use_ them.

They set up their own little social network. Suddenly, it’s easy for people to communicate by text. Suddenly, everyone else gets a sense of just how unbelievable his brother is.

The night after the announcement, they went out to celebrate—W.D. stubbornly sticking to his milk while Sans had enough alcohol for the both of them—and came home covered in residual magic from all the kisses. _i got, uh, seven,_ Sans had laughed. _how about you?_

W.D. had smirked and held up nine fingers.

It was the happiest Sans had ever seen him.

Most people might take things easy for a while after something like that. Honestly, W.D. could’ve never worked another day in his life and he’d still be hailed as a hero. He could make the history books by simply standing still.

His brother was not most people. His brother was just appointed Royal Scientist. He was the youngest and most accomplished person in the building he created.

One day in the canteen, Sans’ phone lights up with a message:

_LUNCH IN MY OFFICE._

He practically skips there.

*

A late-night snack run reveals that his brother still isn’t home.

He’s not surprised, really; the report this morning showed only a slight increase in the Core’s overall energy capacity. The method’s not a _failure,_ but they won’t be breaking barriers with it any time soon. It’s _not_ a failure—it’s not—but partial success and failure equate to the same thing, as far as his brother is concerned.

W.D. will camp out at the Core until he thinks of the next approach, and as Sans searches for his phone, he is very aware of the fact that _come home_ probably won’t meet with nearly as much success as _w.d., do you want anything?_

He’s planning to try the former anyway. That is, until he flips it open and sees that he’s been beaten to it.

The text reads:

_WHEN YOU WAKE UP, CHECK UNDERNET._

Sans groans.

He logs on to find what looks to be a full-length report, pasted into the tiny message box on his tiny phone and god, he wouldn’t have to deal with this if W.D. would give up his damn desktop password. Sans squints his way through each paragraph, searching for the salient details, only to find that W.D.’s next idea involves, well—a blast from the past.

*

It had been Sans’ pet project.

Where W.D. studied energy conversion and the balance of things, Sans had long since turned an eye to time. With his own machine, he got as far as being able to send small objects to a relatively accurate point in a single direction—backwards—before hitting a wall, progress stuttering to a halt.

And then one day W.D. knocked on his door and informed him that he’d just had an interesting chat with the King over tea.

Once they started work on the Core in earnest, the machine became an afterthought, just one more thing he moved over to the new building when the storerooms were finished. Now and then he’d collapse on the couch at home after work, only to become the victim of a well-placed whoopee cushion, and think of it warmly through his laughter. A little fiddling with time and space and finally, he had someone who’d dare to prank the master—though getting back at him was proving to be a challenge.

And that’s what he thought the machine was destined to be, in the end. One very elaborate prop.

His brother had other ideas. The whole time, Sans had been thinking in terms of giving; sending stuff through. W.D. had thought, what if they instead tried to _take_ something?

A small amount of the required energy taken from multiple points in time. Even if the machine could only go backwards, they could start at, say, yesterday, when Sans has having lunch in the cafeteria, harvest some of the residual magic in the air, then go back to an hour before that, where that same magic is still there because they _haven’t taken it yet,_ and. . .

Take it again.

Hell, all that would matter was that they were going backwards each time; if they went back a couple of years and then moved in just fractions of a second, how many barriers would they be able to break with the kisses left on his face?

Tonight, W.D. ran it through all the usual equipment, looking for a suitable source, because if they’re going to try and siphon something, they’ve got to be able to _target_ it properly, but—

_PHOTON READINGS NEGATIVE._

Apparently the usual equipment doesn’t pass muster across space time.

His brother’s idea is to build a _monitor._

*

He tells Suzy to get everyone else in the room. The first report is coming through.

They are, of course, expecting to see one near-infinitely long line, from which they can map out the specifics.

It looks that way, initially. The first fluctuation is a subtle little thing lying at least a year into the future; Sans is the one who catches it. It gets them all talking, gets them scanning further ahead, where it all comes to light: countless knots in the thread, some small little loops and others _vast,_ huge spans of time folded to circle back on themselves.

Sans remains silent as everyone starts guessing at the cause and worse, the _implications,_ pretending it’s not obvious. He _can’t_ speak; he’s too busy staring at the very, very real expanse of black where everything is swallowed up.

Eventually, W.D. shakes him by the shoulder, makes some gesture; his head feels numb and it just doesn’t compute. His brother has to resort to passing him a note.

_TREAT IT LIKE A DEADLINE._

Sans huffs a half-formed, disbelieving laugh.

As he’s crawling into bed that evening, he glues it to his headboard.

*

It’s strange to think about, but he can’t recall another time when they collaborated to this extent. It’s the first time his and W.D.’s specialties have been required in nearly equal measure, the first time they’ve jointly led things; through it all, he can’t help but feel embarrassed at the frequency with which they bump shoulders and miscommunicate.

Changing the direction of transfer is doable, but the machine isn’t the easiest thing to repurpose. W.D. has made his own blueprints: by the time they finish making all the necessary modifications and get it hooked up to the extractor, only a few vestiges of Sans’ design remain.

They start the cycle of trial and error; for each failed attempt, a readjustment. Mistakes are made, but overall, there is an underlying current of calm to each and every action. Everyone is thinking the same thing, even if only Sans ever voices it:

_hey, we all know it’ll work._

Only when the machine outright chokes its way to a noisy death do the signs of desperation start to show, standing stark in the short breaks they take from trying to repair it. Suzy pops a candy in her mouth only to start chewing slower, and slower, eventually spitting it in the bin as if it was licorice. Sans’ sipping on his ketchup has been positively _restrained._

He doesn’t know when W.D. last ate. His brother keeps dodging the question.

The truth is, his pet project has turned feral and sunk its teeth into them all.

Sans calls at W.D.’s office early one morning to just talk, about _anything,_ and finds the room empty. More than that, though, what twists his gut is all the crumpled-up pages he can see scattered across his fastidious sibling’s floor. He comes in to pick them up, and notices the notepad left out on the desk.

He expects a note.

What he gets is a page covered in pen-drawn circles, swirls and loops, on each other and inside one another and everywhere.

*

There’s a bit of irony to it: in order to see what happened, they have to plunge the entire Underground into darkness. Flip the switches, dial everything back. Emergency shutdown.

Sans _knows_ what’s happened, sure as anything, the moment he hears the alarm. Something foreign entered the system, throwing the Core’s temperature off-balance. No prizes for guessing what.

He and Suzy are the ones to go down to the surface floor. The air is still completely saturated with magic—really, you’re supposed to wait at least three days—and it presses down on them with near-suffocating force. They need to be quick, or they risk passing out down here; yet, Sans is shuffling.

He picked Suzy to come along because she can't carry him.

Once he’s out, it’d be painless.

That’s what he’s thinking, right up until the point where they _find_ his brother, slumped on a platform. Naked and blackened to a crisp and _alive,_ still a complete thing.

Suzy screams, “Dr. Gaster!”

And Sans takes a sudden, sharp breath and prepares to play with gravity.

*

The break room isn’t ideal, but it’s the best place they have. They lay him across the couch.

Sans starts barking orders at them— _go get some food, go see if you can salvage the power. hey, you know some green, right?_

As her magic begins to coalesce, Suzy frets: “God, how did a civilian even get in here?”

*

The migraine is—no contest—the worst thing he’s ever felt, but the thought of the alternative has him embracing it, chanting _W.D. Gaster, Royal Scientist, my brother_ over and over and over, until he has a brighter idea and rifles for his wallet.

He fishes for the picture and unfolds it, spreading out the creases as he does his best to pin the image to his mind’s eye. Sans stares at it as if to burn a hole through it, stares at it until each and every blurred colour is painted over the black when he closes his eyes.

Then he flips the picture over, pulling a pen from his pocket.

*

They’re all too skittish to take the risk and ask why he’s keeping a ‘round-the-clock vigil by the random unfortunate who somehow found himself swimming in magical electricity. They take their lunch and their talk elsewhere.

Sans has pretty good hearing, though. The running theory is that he hitched a ride on an ice cube, wanting to go out all _dramatic-like._

Stressed people aren’t very funny.

His brother’s bones are mottled with white all over, now. Before long, he’ll be back to normal. At least, physically.

Sans doesn’t know where to begin with _mentally._ W.D. won’t want to _talk_ about it, of course, so it’s all up to Sans, and Sans is teetering between either going along and pretending there was an _accident_ with W.D., or going _off on him_ and asking whatever the fuck happened to _‘TREAT IT LIKE A DEADLINE’._

Ordinarily, he thinks he’d lean towards the former, but lately he’s had more than his fair share of amnesia and _not knowing,_ and there’s another thing that he’s going to have to explain somehow, some way.

Still, he’s not really surprised when his brother first cracks an eye open and every little thing he had brewing just. . . evaporates.

When all Sans can think to do is take a cup of water from the cooler and offer it to him.

“THANK YOU,” his brother rasps.

And Sans doesn’t quite _drop_ it, but he comes close.

*

A part of his brain—a tad slow, or in denial, or maybe just aware of what’s really important, notes:

_so he was a papyrus._

 

**Author's Note:**

> [My blog.](http://good-times-new-roman.tumblr.com/)


End file.
